The combat uses for helicopter aircraft have changed dramatically over the years to include contact with opposing forces, including reconnaissance and combat aircraft assistance of troops on the front line. This type of use subjects helicopters to numerous threats, and therefore new helicopter designs incorporate offenses weapons, such as gatling guns and rocket launchers.
Initially, the primary control of helicopter weapons was accomplished by the pilot adjusting the aircraft attitude prior to firing. Correction for misses was accomplished by the pilot adjusting the attitude of the aircraft prior to expending additional ordinance. As technology developed, tracking and sensing systems were used to locate a target or target area and determine the aircraft attitude necessary to aim the weapon so as to account for outside forces acting on the ordinance, e.g., wind, aircraft speed, etc. Such a system typically displays a "cross hair" indicative of the actual aircraft attitude and a geometric shape indicative of the required aircraft attitude to provide a high probability of striking the target with the weapon. The pilot is required to maneuver the aircraft so as to place the cross hair in the firing solution defined by the shape prior to firing the weapon. The aiming instructions, e.g., cross hair and geometric shape, are typically displayed on a control panel, a heads up display, or helmet mounted display which provides the pilot with the visual information relating to the target position, aircraft attitude, heading, speed, and altitude.
To further improve weapons delivery accuracy, a system has been developed which simultaneously controls aircraft yaw attitude, pitch attitude, and the firing of aircraft mounted weapons to thereby coordinate the accurate delivery of ordinance at specific target coordinate within a selected target area. Such a system is described and claimed in commonly owned, co-pending U.S. patent application Ser. No. 07/967,308, entitled "Helicopter Integrated Fire and Flight Control Having Coordinated Area Bombing Control". This system provides azimuth and elevation error signals which replace the aircraft yaw attitude feedback error and pitch attitude feedback error for controlling the aircraft to assume an attitude based on a firing solution. Once the aircraft has attained a proper firing attitude, a firing signal is provided for weapons release. The aircraft then assumes the firing attitude corresponding to the next target location.
When the pilot controls the aircraft attitude for a ballistic firing solution, or if an integrated fire and flight control system automatically controls the aircraft attitude for a ballistic firing solution, the aircraft assumes a rearward acceleration because of the upward pitch angle. For certain weapons, e.g., a 70 mm (2.75 inch) rocket with fixed pods, the aircraft may be required to achieve up to a 21.degree. nose-up attitude prior to weapons release. Because of the large rearward acceleration which is attained when assuming the large nose-up attitude, the pilot typically performs a pre-launch forward acceleration maneuver. The pilot uses best pilot judgment and careful attention to ground and obstruction clearance when making the maneuver. In reduced visual conditions, the maneuver is quite hazardous, and pilots often increase altitude as a result. The increase in altitude reduces the terrain masking of helicopter position and may contribute to reduced survivability.